A composite charged particle beam device, which is provided with both a scanning electron microscope (SEM) and a focused ion beam (FIB), has a feature that a region which is processed (or being processed) using a focused ion beam can be observed in situ with a SEM at high resolution. Therefore, it is an essential tool in manufacturing samples for transmission electron microscope observation and also in various industrial fields, such as the field of semiconductor, the field of material sciences, and the field of medicine where nanometer-order micro-processing is required.
Cited literature 1 discloses an objective lens for an electron microscope system having a minimum magnetic field outside the objective lens.